{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-56641","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-12-27T15:00:39.839Z","datePublished":"2024-12-27T15:02:42.958Z","dateUpdated":"2026-08-05T11:45:40.041Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:45:40.041Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: initialize close_work early to avoid warning\n\nWe encountered a warning that close_work was canceled before\ninitialization.\n\n  WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0\n  Workqueue: events smc_lgr_terminate_work [smc]\n  RIP: 0010:__flush_work+0x19e/0x1b0\n  Call Trace:\n   ? __wake_up_common+0x7a/0x190\n   ? work_busy+0x80/0x80\n   __cancel_work_timer+0xe3/0x160\n   smc_close_cancel_work+0x1a/0x70 [smc]\n   smc_close_active_abort+0x207/0x360 [smc]\n   __smc_lgr_terminate.part.38+0xc8/0x180 [smc]\n   process_one_work+0x19e/0x340\n   worker_thread+0x30/0x370\n   ? process_one_work+0x340/0x340\n   kthread+0x117/0x130\n   ? __kthread_cancel_work+0x50/0x50\n   ret_from_fork+0x22/0x30\n\nThis is because when smc_close_cancel_work is triggered, e.g. the RDMA\ndriver is rmmod and the LGR is terminated, the conn->close_work is\nflushed before initialization, resulting in WARN_ON(!work->func).\n\n__smc_lgr_terminate             | smc_connect_{rdma|ism}\n-------------------------------------------------------------\n                                | smc_conn_create\n\t\t\t\t| \\- smc_lgr_register_conn\nfor conn in lgr->conns_all      |\n\\- smc_conn_kill                |\n   \\- smc_close_active_abort    |\n      \\- smc_close_cancel_work  |\n         \\- cancel_work_sync    |\n            \\- __flush_work     |\n\t         (close_work)   |\n\t                        | smc_close_init\n\t                        | \\- INIT_WORK(&close_work)\n\nSo fix this by initializing close_work before establishing the\nconnection."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - The affected code is the SMC (Shared Memory Communications) protocol connect path, driven entirely by a remote peer's CLC/LLC messages, and the racing link-group teardown is itself triggerable by peer-sent LLC DELETE_LINK(ALL), LLC protocol violations, or a CLC DECLINE with the first-contact flag. No local access to the target is required for the attacking peer.\nAC:L - The remote peer controls both sides of the race — it dictates when the client executes smc_conn_create() by timing its CLC Accept reply, and it can force __smc_lgr_terminate() at will via an LLC DELETE_LINK ALL or protocol violation — and it can retry across the many connections an LGR multiplexes until the window is hit.\nPR:N - SMC performs no authentication of its own; a peer completing the ordinary TCP/CLC handshake needs no credentials or privileges on the target system. Locally, AF_SMC socket creation also has no capability check in smc_create()/__smc_create().\nUI:N - The condition is hit during normal, automatic SMC connection establishment and link-group termination handling; no victim action such as opening a file or mounting anything is needed.\nS:U - The warning and any resulting panic occur in the kernel's own SMC/workqueue context, with no crossing of a virtualization, IOMMU, or other security-authority boundary.\nC:N - __flush_work() returns immediately at WARN_ON(!work->func) without dereferencing or exposing any data; there is no out-of-bounds read, uninitialized-memory disclosure, or pointer leak beyond the standard splat.\nI:N - No memory is corrupted — close_work is zero-initialized and was never queued, so the aborted cancel leaves no dangling state and provides no write primitive or control-flow influence.\nA:H - The WARN_ON is a kernel warning raised from the smc_lgr_terminate_work worker, which panics the system outright on the widely deployed panic_on_warn=1 configuration and can be triggered repeatedly by the peer, yielding a remote denial of service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/af_smc.c"],"versions":[{"version":"46c28dbd4c23c3f7fa37f5ea48772af79c9cc40e","lessThan":"f0c37002210aaede10dae849d1a78efc2243add2","status":"affected","versionType":"git"},{"version":"46c28dbd4c23c3f7fa37f5ea48772af79c9cc40e","lessThan":"6638e52dcfafaf1b9cbc34544f0c832db0069ea1","status":"affected","versionType":"git"},{"version":"46c28dbd4c23c3f7fa37f5ea48772af79c9cc40e","lessThan":"0541db8ee32c09463a72d0987382b3a3336b0043","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/af_smc.c"],"versions":[{"version":"4.12","status":"affected"},{"version":"0","lessThan":"4.12","status":"unaffected","versionType":"semver"},{"version":"6.6.66","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.5","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.13","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.6.66"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.12.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.13"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f0c37002210aaede10dae849d1a78efc2243add2"},{"url":"https://git.kernel.org/stable/c/6638e52dcfafaf1b9cbc34544f0c832db0069ea1"},{"url":"https://git.kernel.org/stable/c/0541db8ee32c09463a72d0987382b3a3336b0043"}],"title":"net/smc: initialize close_work early to avoid warning","x_generator":{"engine":"bippy-1.2.0"}}}}